Changing the range of the coordinates on Blender's Viewport
My suggestion is to use the scale option.

In the image below the real world block is 480 x 480 km, scale is used to map it onto 16 x 16 blender units. Once that choice is made, divide your coordinates by

scene.unit_settings.scale_length


when importing, calculated to give you the correct dimensions in the unit of your data.